Stars $35 6-handed....Turn play?

[Jonathan]

How should I continue on the turn in this situation?
The BB has slow played a number of prior hands

PokerStars No-Limit Hold'em Tourney, Big Blind is t100 (3 handed) FTR converter on zerodivide.cx

BB (t2309)
Hero (t2868)
SB (t3823)

Preflop: Hero is Button with 7[img]/images/graemlins/spade.gif[/img], A[img]/images/graemlins/spade.gif[/img].
<font color="#CC3333">Hero raises to t300</font>, SB calls t250, BB calls t200.

Flop: (t900) 2[img]/images/graemlins/spade.gif[/img], 7[img]/images/graemlins/diamond.gif[/img], 5[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(3 players)</font>
SB checks, BB checks, <font color="#CC3333">Hero bets t900</font>, SB folds, BB calls t900.

Turn: (t2700) 6[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
BB checks,

On the flop, I would normally bet between 1/2 the pot
up to the full pot. In this case, I chose to pot it
because of the draw heavy board, and I'm happy to take
it down right away.

Once BB calls this bet, and the straight card comes on
the turn, how should you respond to his check?

Thanks for the input.

Jonathan